1986 Mustang T-Top - Plumb Assignments - The Project Car

February 28, 2007

Let's review automotive theory, if you will. A Mustang, just as any car, is comprised of a series of systems. There's the electrical system, the suspension system, the ignition system, and others. Together, these all collaborate to make the car function as it should; without most of them, a 'Stang would be nearly inoperable.

Now that the engine and transmission are in place in our '86 T-top coupe ("Lowering the Vroooom," March '07, p. 142), we're at a point in the Mustang's reconstruction where we can start taking care of the must-do development of the systems that will make our car work.

The T-top coupe's fuel, air-induction, exhaust, and cooling systems are critical to how its Paxton Novi 2000-blown 347 will operate in the real world. The 'Stang's brake system is another vital element of its overall grand scheme, since we'll be counting on it to slow down our beast from break-neck speeds at the track.

Fabricating and routing stainless steel, braided-, and hard-line hoses, as well as stainless tubing, are the tasks at hand for this segment of our build effort. The systems we're creating allow various fluids and gasses to travel to and from the points they need to reach throughout the car. This development of flow circuits is known as "plumbing" the Mustang, and, in theory, it doesn't differ much from laying out the myriad of pipes and fittings that move water, heat/air conditioning, and exhaust in most homes and buildings.

We're fortunate enough to have some of the best in the high-performance-plumbing businesses based in Southern California, and we called on them for assistance with a few of the systems being covered in this report. Special thanks are a must for Bent Custom Plumbing and Sheetmetal, Fab-Tech Custom Fabrication, Fast Intentions Performance Exhaust, Galpin Auto Sports, JBA Performance Exhaust, Saul "The Surgeon" Gutierrez, and Orme Brothers Hose and Fittings. Everyone made adjustments in their schedules to accommodate our project and meet the critical deadlines.

Plumbing a 'Stang is physically and mentally taxing. It's hard on the body installing tubes in hard-to-reach areas, especially if you don't have the luxury of a shop or tools that make it easier; it's also hard on the mind trying to map out where and how things should be routed in the car so it looks good, and, more importantly, functions well.

When plumbing your 'Stang, keep bends in the lines and tubes to a minimum. The shortest distance between two points is a straight line, and that theory is important when it comes to the way certain properties move in, around, and out of a car. Knowing what to use for the different types of plumbing systems in your 'Stang-hose diameters, pressure ratings, material, and so on-is also important.

This project is about using the right stuff to build our street/strip 'Stang, and showing exactly what comprises the right stuff and how to use it. Remember, we've been building our coupe with a Drag Week (five-day/1,500-mile, real-world street/strip endurance challenge) mentality, so we've set an unofficial minimum 300-mile-per-day standard that every aspect of the car must meet.

Follow along as we work on getting our four-eye's flow right.

FuelThe fuel system is the liquid lifeline for any car, and we're making sure the plumbing for our ride's fuel delivery is topnotch. We've already given you the lowdown on the 14-gallon fuel tank by Rick's Hot Rod Shop that incorporates Aeromotive's 600 lb/hr, A-1000 EFI fuel pump and 100-Micron fuel filter inside it ("Tech Inspection," Jan. '07, p. 180), but there's a lot more to the fuel system that needs to be highlighted.

From the tank, AN (this stands for Army/Navy) -8 fittings and a steel-braided hose is used for feeding fuel forward. The -8's diameter is about 131/432 of an inch, which is the minimum recommended for 300-, to 600hp power-adder applications. Full-on race cars use AN -10 line that is approximately 11/42-inch diameter for fuel delivery, as more exotic combinations count on getting every bit of fuel volume possible.

The main fuel line passes through a Barry Grant fuel cooler, then flows into a Y-block by Overkill Performance. The Y-block divides the fuel feed across two lines that supply the Aeromotive fuel rails and RC Engineering 650cc injectors sitting atop the 347's intake manifold.

We're setting up the coupe's fuel system as a return-style deal, meaning fuel that isn't metered through the injectors circulates through Aeromotive's A-1000-6 bypass regulator and back to the tank. This process keeps fuel flow steady-especially under hard accelerating and braking-and it will also keep the fuel's temperature cooler when we drive the coupe on the streets and freeway.

Air IntakeFor most engines, if fuel is one side of the induction coin, air, or inlet-air, is the other. Since we'll be boosting the air charge for our stroker with a 15-plus pound boost blast from Paxton's Novi 2000 supercharger, it's imperative we get as much air as possible into the blower and make sure its exit to the throttle body is smooth and direct.

The small-diameter tubing provided in the Novi 2000 Tuner Kit is perfect for achieving eight or so pounds of boost. Since our plan is to make boost above and beyond that range, we decided to use tubes (4-inch inlet, 3-inch discharge) that will be more efficient than those provided in the blower kit. Danny Akre of Fast Intentions Performance Exhaust in Northridge, California, is the mastermind behind the stainless steel pieces of art seen here. While we watched Danny plumb our supercharger's airflow, he explained the importance of keeping the path simple. "You want to have as small a number of bends in the tubes as possible when you set up inlet-air systems." A direct-as-possible route maintains a steady air charge, which is what we want for our blown combination.

ExhaustAs you may already know, fuel and air are burned during the combustion process. Exhaust is the basic end-product of combustion; based on our engine's makeup ("Big-Bore Score," Dec. '06, p. 58), we'll need an exhaust system that will quickly and efficiently scavenge gasses out of the exhaust ports of the high-flowing AFR 205s that are bolted on the coupe's 347.

A really good, high-performance exhaust system for a blown 'Stang is based around 131/44-inch headers. Most headers are made of mild steel, but the exhaust plumbing can be crafted out of stainless steel or aluminized steel tubes. Both have greater corrosion resistance.

We're happy about the way we've been able to bring new Fox Mustang technology to the forefront during the last few months.

One of the nuances of using raised-port cylinder heads is the limited selection of "shelf" headers available. While they're not true high ports, AFR's street/strip heads have exhaust ports that are approximately 11/48 inch taller than stock cylinder heads. To put it bluntly, enthusiasts usually have to get custom headers made, which can be costly.

Due to an insane schedule around the time these new headers were developed, we couldn't cover the step-by-step build process. But the finished products are bad to the bone, and are complemented by a 3-inch, X-shape crossover tube and JBA's stainless steel mufflers.

CoolingThe cooling system is a major player in our all-world 'Stang. To effectively handle its street driving and dragstrip assignments, the car needs equipment to keep both systems operating at their optimal temperatures by removing heat from the engine and the transmission.

We faced a challenge with our Mustang's cooling system. Since we're using a beltdrive setup for the cam timing, and with our car not having power steering, air conditioning or other serpentine-belt-dependent accessories, we have to use an electric water pump for our engine.

In any vehicle, the water pump transfers coolant from the radiator, through the engine, and back into the radiator. Controlling heat is always an issue for street 'Stangs, especially those similar to ours that are driven daily in high-temperature areas. To supplement the electric water pump, we know our combination requires the superior cooling ability of an aluminum radiator.

We spoke with the folks at Afco Racing Products and Meziere Enterprises about combining an electric pump with a bolt-in aluminum radiator for Fox 'Stangs, and the part they've developed is outstanding. Here is another Fox-specific innovation that has come about as a result of this project effort: Afco's direct-fit, Performance Series two-row aluminum radiator (PN 80270FN), featuring an optional Meziere high-flow, remote electric water pump (PN WP362) that's built into the radiator. We have seen this type of cooling technology on some NMRA Pro 5.0 Mustangs, but the big difference is that those systems use wafer-thin radiators and fans since they only have to support 6- and 7-second quarter-mile blasts.

Our coupe is being built for the quarter and the road, so we're pumped that this type of street-specific, racing-influenced cooling product featuring a standard-sized 'Stang radiator, high-flow pump, and large cooling fan/shroud has been created and combined in one unit.

We also have heat concerns about our Performance Automatic AODE transmission and Precision converter. Keeping these components cool is important, so we're plumbing B&M Racing's Hi-Tek SuperCooler (PN 70297) into the project car's cooling scheme. Similar to the engine's radiator, the Hi-Tek cooler includes an electric fan to keep the transmission-fluid temps in check as we roll down the highway.

A humongous AN -16 (equivalent to 111/42-inch) steel-braided hose serves as our coolant line from the radiator/water pump and the engine, and AN -8 plumbing shuttles tranny fluid between the cooler and transmission.

BrakesThe brake system of our coupe is fairly simple from a plumbing perspective. We have done away with the OEM power brakes and are using a Wilwood manual-brake setup. For drag racing purposes,we're adding a Moroso antiroll system (PN 44050) to keep the front wheels locked when we do our burnouts.

Aluminum, mild steel, and stainless steel hard line are the preferred forms of ducting for street-'Stang brake systems. We're using 304-grade stainless steel in the coupe, mainly because it's the most durable and won't break or fail under the driving and racing stresses we'll impose on the system.

Manipulating stainless hard line is an art form. The material is hard and difficult to bend, so it's important to make sure measurements are correct before you create brake lines. Screwing up can become expensive when using stainless steel.

Mark Bohlen, owner of Bent Custom Plumbing and Sheetmetal in Chatsworth, California, is a 12-year veteran at working the hard line. Mark creates brake lines and other automotive plumbing that are nothing short of masterpieces. A wicked example of Mark's talents can be seen on the cover and inside the Sept. '06 issue of Hot Rod magazine; Mark is responsible for the stainless steel hard lines that run rampant across all points of David Freiburger's twin-turbocharged Brand-X/"F-Bomb" small-block.

Mark set up our car with 31/416-inch brake lines made from the aforementioned stainless steel, as well as AN -3 braided hose. This brake plumbing has officially been classified as "sick" by those who have seen it in person, which, in 'Stangbanger language, is one of the highest expressions of approval given.